chore: prepare v0.3.0 release

[knisar]

Prepare v0.3.0 from the merged changes since v0.2.0. Update the shared package/report version, point the README's pinned-install example at the new tag, and credit @KunyangZhang's merged #74 contribution in the permanent contributor list.

The GitHub release will summarize the shipped changes and credit all 16 outside contributors in this release interval. Issue #38 remains unresolved and will be explicitly documented as a known limitation. The next release is planned for October 1.

Validation

Checks ran in a fresh Python 3.13 environment with .[dev] installed at version 0.3.0:

• python -m pytest -q: 332 passed, 15 skipped. The skips require optional Weave dependencies; CI covers both supported Weave environments.
• python -m ruff check --select E9,F63,F7,F82 .: passed with Ruff 0.16.6.
• reuse --no-multiprocessing lint: passed with REUSE 6.2.0; 134/134 files have license and copyright information.
• git diff --check, git diff --cached --check, and git diff --check refs/remotes/upstream/main...HEAD: passed.
• python -m build --no-isolation --outdir /private/tmp/rai-v030-build: built the wheel and source distribution with build 1.6.0.
• Installed the built wheel in a separate clean environment. Distribution/import version parity is 0.3.0, public adapter/scorer imports and rai --help pass, and uv pip check reports compatible dependencies. Inspected both archives for version metadata and expected packaged paths.

Prepared with AI assistance.